Sealing device for an article handling machine

ABSTRACT

Sealing device ( 11 ) for sealingly interfacing two adjacent blocks ( 2, 3 ) of an article handling machine, each provided with an aperture ( 6, 9 ), said sealing device ( 11 ) comprising a resilient static sealing joint ( 12 ) mounted along the edge ( 7 ) of one aperture ( 6 ), wherein the sealing joint ( 12 ) is hollow, and wherein the sealing device ( 11 ) further includes an injection valve ( 14 ) for injecting air in the sealing joint ( 12 ) to inflate it.

FIELD OF THE INVENTION

The invention relates to a sealing device for sealingly interfacing twoadjacent blocks of an article handling machine.

BACKGROUND OF THE INVENTION

Article handling machines are often manufactured in several parts(called blocks) assembled to form a one-piece manufacturing line.

Such a design (called modular design) is satisfactory because itfacilitates transportation of the different blocks (which may come fromdifferent manufacturing places) to the final destination where themachine is assembled.

However, assembly of the different blocks may be problematic, especiallyfor handling machines which define a closed inner volume. For example,in the container industry, aseptic filling machines require that theinner volume be isolated from the outer environment to preservecontainers from bacteria.

In such a case, sealing joints are generally provided at the interfacebetween two adjacent blocks, around an aperture in the blocks forallowing passage of the articles.

Such a solution seems satisfactory, but leaks are often witnessed inlarge-sized machines, due to the distortion of the blocks under thestress they undergo during assembly (the ground may not be perfectlyplanar) and operation (e.g. vibrations may occur) of the machine.

There is therefore a need for improvements in sealing devices providedat the interface between adjacent blocks of an article handling machine.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a sealing device havingincreased sealing properties.

It is another object of the invention to provide a sealing device havingenhanced reliability.

Accordingly, there is proposed a sealing device for sealinglyinterfacing two adjacent blocks of an article handling machine, eachprovided with an aperture, said sealing device comprising a resilientstatic sealing joint mounted along the edge of one aperture, wherein thesealing joint is hollow, and wherein the sealing device further includesan injection valve for injecting air in the sealing joint to inflate it.

The above and other objects and advantages of the invention will becomeapparent from the detailed description of preferred embodiments,considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial perspective view showing a block of an articlehandling machine provided with a sealing device.

FIG. 2 is a sectional view showing assembly of two blocks interfacedwith a sealing device, shown in a non inflated state.

FIG. 3 is a sectional view showing assembly of the blocks of FIG. 2,interfaced with the sealing device shown in an inflated state.

DESCRIPTION OF PREFERRED EMBODIMENTS

Turning now to the drawings, there is shown a frame element 1 of anarticle handling machine 2, e.g. a container handling machine. Themachine is modular, and therefore built by assembly of severalfunctional blocks 2, 3 (e.g. for supporting a container feeding unit, acontainer rinsing unit, a container filling unit and a container cappingunit) juxtaposed and coupled by means of removable fixation means suchas bolts.

The frame element 1 shown on FIG. 1 is a lateral wall of a machine block2, ready to be interfaced with one adjacent block 3. The wall 1comprises an overall chassis 4 formed of welded metallic beams 5 ofrectangular or square section.

There is defined in the chassis 4 an aperture 6 through which thearticles are to be transferred from one block 2 to the adjacent one 3.In one embodiment, illustrated on FIG. 1, the aperture 6 has arectangular shape (with rounded corners) and is limited by a rectangularedge 7 defined by a cut-out in a plate 8 fixed to the chassis 4.

Correspondingly, the adjacent block 3 defines an aperture 9 of similarshape and dimensions, formed by a rectangular cut-out in a plate 10fixed to a chassis of the adjacent block 3. Once the blocks 2, 3 areassembled, both apertures 6, 9 are coincident, as illustrated on FIG. 2.

As depicted on the drawings, there is provided a sealing device 11 forsealingly interfacing the adjacent blocks 2, 3, mounted on the chassis 4of the block 2 around the aperture 6.

More precisely, the sealing device 11 comprises a resilient staticsealing joint 12, made e.g. of rubber, mounted along the edge 7 of theaperture 6.

The sealing joint 12 is hollow and defines an inner air chamber 13. Thesealing device 11 further includes an injection valve 14 for injectingpressurized air (or any equivalent inert gas) in the air chamber 13 toinflate the sealing joint 12.

As depicted on FIG. 2, the injection valve 14 comprises a nozzle 15attached to the sealing joint 12, for putting the air chamber 13 incommunication with a pressure source.

It can be seen on FIG. 2 that, before it is inflated, the sealing joint12 presents a U-shaped section. It comprises a flat back wall 16, fixedto a planar outer face 17 of the plate 8 (e.g. by means of glue), anouter wall 18 to which the nozzle 15 is attached, an inner wall 19limiting the aperture 6, and a U-shaped front wall 20 linking the outerwall 18 and the inner wall 19 and protruding inwards into the volumelimited by the back wall 16, outer wall 18 and inner wall 19.

The sealing device 11 further comprises a frame 21 fixed to the outerface 17 of the plate 8 and surrounding the sealing joint 12, in contactwith the outer wall 17 thereof, to confine the sealing joint 12 wheninflated.

As depicted on FIG. 2, the surrounding frame 21 is adjacent the beams 5of the overall chassis 4, thereby increasing rigidity of the wall 1.

The machine blocks 2, 3 are sealingly assembled as follows.

First, the blocks 2, 3 are placed adjacent to one another, so that theapertures 6, 9 are coincident. The plate 10 of the adjacent block 3 maybe in contact with the chassis 4 of the block 2, as depicted on FIG. 2.The blocks 2, 3 are then fixed to one another, e.g. by means of fixationbolts inserted in holes provided in coupling plates 22. Once the blocks2, 3 are fixed together, pressurized air is injected via the nozzle 15in the air chamber 13, so that the sealing joint 12 is inflated, untilthe front wall is bent outwards to a point where it exerts on the plate10 of the adjacent block 3 a pressure all around the aperture 9 (FIG.3), thereby sealing the interface between the blocks 2, 3. Under thepressure of the sealing joint 12, the adjacent block 3 may be slightlyspaced from the chassis 4, as depicted on FIG. 3.

The back wall 16 and outer wall 18 remain still, since they are confinedby the plate 8 and the surrounding frame 21, respectively, so that onlythe inner wall 19 and front wall 20 are bent, thereby conferring thesealing joint 12 the general shape of a bean (FIG. 3).

Value or the air pressure in the air chamber 13 is left to theappreciation of the skilled person. Pressures comprised between 2 and 4bars seem convenient in most applications.

The sealing joint 12 is preferably made of silicon, and has a wallthickness e.g. in the range of 2-5 mm.

Accordingly, there is provided a sealing device allowing good andreliable performance for interfacing two blocks in article conveyingmachines.

Of course, the invention is not limited to the disclosed embodiments. Inparticular, the skilled person may adapt the shape of the sealing joint12 to the edge of the aperture 6, and/or the section of the sealingjoint 12 to the surfaces on which it is provided to exert a pressure.

1. Sealing device for sealingly interfacing two adjacent blocks of anarticle handling machine, each provided with an aperture, said sealingdevice comprising a resilient static sealing joint mounted along theedge of one aperture, wherein the sealing joint is hollow, and whereinthe sealing device further includes an injection valve for injecting airin the sealing joint to inflate it.
 2. Sealing device according to claim1, wherein, before inflated, the sealing joint has a U-shaped section.3. Sealing device according to claim 1, wherein the sealing joint isfixed to a planar surface of one block, adjacent said aperture. 4.Sealing device according to claim 3, wherein the sealing joint is gluedto said planar surface.
 5. Sealing device according to claim 1, furthercomprising a frame surrounding the sealing joint.
 6. Sealing deviceaccording to claim 5, wherein the frame is fixed to one block. 7.Sealing device according to claim 1, wherein the injection valvecomprises a nozzle for putting an inner volume of the sealing joint incommunication with a pressure source.
 8. Sealing device according toclaim 7, wherein said nozzle is fixed to an outer wall of the sealingjoint.